The Hedonic Treadmill Theory
Empirical evidence suggests that we have a tendency to adapt to both positive and negative life events. Often, this results in a return to our preexisting level of happiness, known as our happiness setpoint. In his novel Enduring Love, Ian McEwan (1997, p. 141) captures this idea succinctly:
“People often remark on how quickly the extraordinary becomes commonplace… We are highly adaptive creatures. The predictable becomes, by definition, background, leaving the attention uncluttered, the better to deal with the random or unexpected.”
Brickman and Campbell introduced the metaphor of the hedonic treadmill in their 1971 paper “Hedonic Relativism and Planning the Good Society.”
For their research, Brickman and Campbell (1971) relied on stimulus psychology and models of automatic habituation. According to their findings, we generally experience short-term spikes in happiness following positive events (such as winning the lottery). Eventually, however, our levels of subjective wellbeing return to our pre-event state baseline.
Imagine buying your dream car—a shiny, brand-new luxury vehicle. Initially, you are overwhelmed with joy and satisfaction. The car’s powerful engine and luxurious features bring you immense pleasure, and you feel a surge of happiness each time you get behind the wheel.
However, over time, the novelty wears off, and the car becomes a familiar part of your daily routine. You no longer experience the same level of excitement and delight you felt during the early days of ownership.
According to the hedonic treadmill theory, we adapt both to positive or negative life events, and our happiness levels eventually return to our initial set point.
Brickman and Campbell studied a group of lottery winners and a group of people who experienced terrible accidents with life-changing effects. In their 1971 study, their finding was that “lottery winners and accident victims both returned to their pre-event happiness levels within a few months or years” (as cited in Diener et al., 2006, p. 306).
Hedonic adaptation, then, involves the restoration of baseline levels of happiness following positive or negative life events.
It follows that material possessions or external circumstances alone cannot sustainably increase or decrease our long-term happiness.
Sheldon and Lucas (2014, p. 4) define hedonic adaptation as “the tendency to cease noting a particular stimulus over time so that the stimuli no longer have the emotional effects they once had.”
In other words: If we are exposed to the same stimuli over time, the quality of our experience and our response to these stimuli change.
Various psychological mechanisms contribute to hedonic adaptation. The most prominent one is the process of cognitive adaptation. It suggests that we adjust our expectations and aspirations to align with our current circumstances (Frederick & Loewenstein, 1999).
Additionally, social comparison theory suggests that we have a tendency to compare our own situation with others’, which can lead to a recalibration of subjective wellbeing (Wills, 1981).
The peak–end rule proposes that we tend to remember and evaluate experiences based on our most intense point and the final moments, rather than considering the overall duration of the experience (Kahneman et al., 1993). Personality traits, such as neuroticism and extraversion, have been found to impact hedonic adaptation, too (Lucas, 2007).
More specific factors that impact the adaptation processes
There are also more specific factors that influence the duration and scale of the adaptation process. The impact of life events on adaptation varies depending on their intensity, novelty, and duration (Diener et al., 2006). Researchers have also highlighted the role of individual differences in genetic predispositions and environmental factors in shaping hedonic adaptation, such as socioeconomic status (Lykken & Tellegen, 1996; Diener & Seligman, 2004).
More recently, Klausen et al. (2022) pointed out some problems with common conceptions of hedonic adaptation in their thought-provoking paper “Many Faces of Hedonic Adaptation.”
They argue that the notion of ‘stimulus’ used in most adaptation theories is based on sensory stimuli but then expanded to include various non-sensory stimuli. Klausen et al. (2022) propose that we need a more complex and diverse concept of the nature of adaptation and should consider switching to a hybrid and process-oriented theory of wellbeing.
Concepts such as selective attention, judgment, articulation, contextualization, and background assumption, as well as coping strategies and social support, need to be considered in theories of hedonic adaptation (Klausen et al., 2022).
Finally, we may also wonder whether the treadmill is a helpful metaphor to begin with. The image suggests being trapped in a cycle of pointless, effortful activities that, quite literally, get us nowhere.
Similarly, the idea of a fixed happiness baseline that is predetermined by our genes or personality type may make us feel hopeless about our agency, efficacy, and ability to change our mental wellbeing. Why bother taking positive, transformative action, we may think, if our happiness level is always already set?
The Hedonic Adaptation Prevention (HAP) Model
These kinds of questions are precisely why researchers have begun to explore ways of counteracting the effects of hedonic adaptation.
Lyubomirsky, Sheldon, and Schkade (2005) have proposed the Hedonic Adaptation Prevention (HAP) model, suggesting that intentional efforts to prevent adaptation can prolong the positive effects of life events. “People may be able to actively prolong or enhance their happiness by preventing themselves from fully adapting to positive events” (Lyubomirsky et al., 2005, p. 120).
According to the HAP model, there are three primary components that influence our happiness set point and capacity to prevent hedonic adaptation.
1. Genetic predispositions
The HAP model acknowledges that genetics play a role in determining our baseline level of happiness. Some of us naturally possess a more positive disposition, making us less prone to hedonic adaptation.
However, this genetic component only accounts for a portion of our overall happiness, and it is the least amenable to change. The HAP model suggests that we should focus on the factors that are clearly within our control to maximize wellbeing.
2. Intentional activities
The HAP model emphasizes the importance of intentional activities to prevent or slow down hedonic adaptation. Lyubomirsky et al. (2005) propose that activities such as expressing gratitude, practicing kindness, and setting and pursuing meaningful goals can lead to sustained increases in happiness.
Another point highlighted in the HAP model is the importance of variety in intentional activities. As Lyubomirsky et al. (2005, p. 123) explain, “When people engage in different activities, they are less likely to habituate to any single one.”
By regularly introducing new experiences and diversifying activities, we can maintain a heightened level of happiness and prevent adaptation.
3. Circumstantial factors
The third component of the HAP model focuses on circumstantial factors that can influence our happiness. These factors include life events, environmental conditions, and social relationships. While some circumstances may be beyond our control, the HAP model suggests that we can actively seek to shape our circumstances to prevent hedonic adaptation.
This all sounds very sensible. It is unsurprising that a core strategy outlined in the HAP model is the practice of gratitude.
Cultivating gratitude for the positive aspects of our life is perhaps the most powerful antidote to hedonic adaptation.
Lyubomirsky et al. (2005, p. 128) write: “Grateful thinking promotes adaptive coping by reducing the impact of the negative aspects of situations, promoting positive appraisals of stressful events, and preventing the decline in positive affect over time.”